ISRO 2016 Electronics (Set - E) 1. How does does the dynamic dynamic resistanc resistance e of diode diode ary with tem!erat tem!erat"re# "re# a. $irect $irectly ly !ro!or !ro!ortio tional nal %. In Iners ersely ely !ro!o !ro!orti rtiona onall c. Ind nde! e!en end dent d. $irectly $irectly to the the s&"are s&"are of tem!era tem!erat"re t"re
2. 'he electric electric eld eld com!onent com!onent of a time harmon harmonic ic !lane !lane E wae traelin* traelin* in a non-ma*netic lossless dielectric medi"m has am!lit"de of 2 +,m. If the relatie !ermittiity of the medi"m is the ma*nit"de of the time aera*e !ower density ector in /,m 2 is a. 1,0 %. 1,120 c. 1,60 d. 1,20
. 'he force on a !oint !oint char*e & 3e!t 3e!t at a distance distance d from from the s"rface s"rface of an an innite *ro"nded metal !late !late in a medi"m of !ermittiity 4 is a. 0 %. &2,164d2 away from the !late c. &2,164d2 towards the !late d. &2,4d2 towards the !late
. 5 materi material al has has cond" cond"cti ctiit ity y of 10 -2 mho,m and a relatie !ermittiity of . 'he fre&"ency at which the cond"ction c"rrent c"rrent in the medi"m is e&"al to the dis!lacement c"rrent is a. H7 %. 80 H7 c. 0 H7 d. 800 H7
. 5 system has fo"rtee fo"rteen n !oles and and two 7eros. 7eros. Its hi*h hi*h fre&"enc fre&"ency y asym!tote asym!tote in its ma*nit"de !lot hain* a slo!e of a. 9 0 0 d:, d:,de deca cade de %. 9 20 20 d:,d d:,dec ecad ade e c. 9 2;0 2;0 d:,d d:,dec ecad ade e d. 9 20 20 d:,d d:,dec ecad ade e
6. 5 1m/ ideo si*nal hain* a %andwidth of 100 H7 is transmitted to a receier thro"*h a ca%le that has 0 d: loss. If the e
=.
/hen the ;01 is reset and the line is HI>H the !ro*ram co"nter !o;ints to the rst !ro*ram instr"ction in the a. Internal code memory %. E?ternal code memory c. Internal data memory d. E?ternal data memory
;. How is the stat"s of the carry a"?iliary carry and !arity @a* a
8. In the *ien com%inational lo*ic F is *ien %y
10.Each transistor in $arlin*ton !air (as shown in Gi*) has h fe D 100. Oerall hfe of com!osite transistor ne*lectin* lea3a*e c"rrent is a. 10000 %. 10001 c. 10100 d. 10200
11.In a *ien networ3 shown in *"re a steady state is reached with switch 3 o!en. 5t tD0 which is closed. $etermine the al"es of I1 I2 and I at t D 0 (in 5m!eres). a. 1 1, 0 %. 1, 1, 1, c. 0 0 0 d. 1 1 1
12.Sim!lify :oolean f"nction re!resented in s"m of !rod"cts of min-terms G(?y7) D m(026)
1.5 system is descri%ed %y the transfer f"nction H(s) D 1,(S S2 3S ) is sta%le. 'he constraints on and 3 are a. J 0 3 K %. J 0 3 J c. J 0 3 J 0 d. J 0 3 K 0
1.Bonsider a "nity feed%ac3 system whose o!en loo! transfer f"nction is >(s) D 3,s(s2 2s 2). 'he Ly&"ist !lot for this system is
1.Eye dia*ram *ies an idea of a. od"lation scheme %. Bloc3 Mitter c. SLR d. 5ll of the a%oe
16.'he si*nal @ow dia*ram for a certain feed%ac3 control system is shown in *"re. Low consider the followin* set of e&"ations for the nodes. 1. ?2 D a1?1 18? 2. ? D a2?2 a;? . ? D a? a?2 . ? D a? a6?2 /hich of the followin* are correct# a. 1 2 and %. 1 and c. 2 and
d. 1 2 and
1=.'he a!!ro!riate o"t!"t fre&"ency of oscillator for R 5 D R: D 2.2 3N and B D 2000 !G a. 110 3H7 %. 108. 3H7 c. 120. 3H7 d. 10;.8 3H7
1;.5 co"nter is desi*ned "sin* -P @i! @o! as shown in *"re. $ene its co"nt se&"ence a. 000 001 010 011 100 Q re!eats %. 100 011 010 001 000 Q re!eats c. 010 011 100 000 001 Q re!eats d. 101 110 111 000 001 010 011 100 Q re!eats
18.5 1 H7 cloc3 si*nal is a!!lied to a -P @i! @o! with DPD1. /hat is the fre&"ency of the @i! @o! o"t!"t si*nal# a. 2 H7 %. 00 3H7 c. 20 3H7 d. 00 H7
20.How many in!"ts Q o"t!"ts does a f"ll adder hae# a. 2 %. 2 c. d. 22
21./hich shift re*ister co"nter re&"ires the most decodin* circ"itry# a. honson co"nter %. Rin* co"nter c. Ri!!le co"nter d. O$ co"nter
22.5 10 %it $5B has ste! si7e of 10m+. /hat is its G"ll scale o"t!"t olta*e and the !ercenta*e resol"tion# a. 10.2 + 0.2
%. 10.2 + 0. c. 10.2 + 0.1 d. 10.2 + 0.1
2.If the in!"t si*nals 5 : and o"t!"t si*nals are shown as %elow then the circ"it element is a. 5L$ *ate %. OR *ate c. LOR *ate d. FOR *ate
2.Gor a 10 %it di*ital ram! 5$B "sin* 00 3H7 cloc3 the ma?im"m conersion time is a. 20; s %. 206 s c. 206 s d. 20; s
2.In di*ital lters how many inter!olated data !oints are inserted %etween sam!les when !erformin* F oer sam!lin*# a. 2 %. c. d.
26.5 5 so"rce *enerates fo"r sym%ols + 1 + - 1 + and 9 + with !ro%a%ilities of 0.2 0. 0. and 0.2 res!ectiely. 'he ariance for this so"rce will %e a. .2 + %. .2 + c. .6 + d. .6 +
2=.'he o"t!"t e&"ialent circ"it of followin* circ"it is a. IL+ER'ER %. 5L$ c. OR d. LOR
2;.5 %inary so"rce in which 0Ts occ"r times as often as 1Ts. 'hen its entro!y in %its,sym%ol will %e a. 0.= %its,sym%ol %. 0.2 %its,sym%ol c. 0.;1 %its,sym%ol d. 0.; %its,sym%ol
28.a?im"m al"e of si*nal to noise ratio of an ; %it 5$B with an in!"t ran*e of 10 olts will %e a. 0 d: %. .; d: c. ;.8 d: d. 8.; d:
0.'he aaila%le !ower re&"ired at a receier antenna I s10-6 watts. 'ransmittin* and receiin* antennas hae *ain of 0 d: each. 'he carrier fre&"ency is >H7 and the distance %etween them is 0 miles. 'he re&"ired transmitted !ower is a. 0.6 /atts %. 0.= /atts c. 0.=; /atts d. 0.2 /atts
1.5n G si*nal at 10.= H7 IG needs to %e di*iti7ed for demod"lation in a di*ital domain. If the %andwidth of this si*nal is 200 3H7 the ma?im"m "sa%le sam!lin* fre&"ency is a. 200 3H7 %. 600 3H7 c. 00 3H7 d. ;00 3H7
2.5 satellite system em!loys USP mod"lation with 0 e?cess %andwidth !er carrier incl"din* *"ard %and. 'he oice channels "se 6 3%!s B codin*. 'he n"m%er of channels s"!!orted %y 6 H7 %andwidth of the trans!onder in %andwidth limited case will %e a. 1000 %. ;00 c. 800 d. 600
.Hammin* codes are "sed for a. :"rst error correction %. Si*nal error correction c. :oth a and % d. Lone of the a%oe
./hich statements is correct for Schott3ey diode# a. B"rrent olta*e characteristics is totally di
.hoto diodes o!erate at a. Gorward %ias %. :rea3down re*ion c. Reerse %ias d. Sat"ration re*ion
6.'he dynamic resistance of diode aries as a. 1,I2 %. 1,I c. I d. I2
=.In a L diode with the increase in reerse %ias the reerse c"rrent a. Increases %. $ecreases c. Remain constant d. Vncertain
;.'he Ly&"ist lter has im!"lse res!onse *ien %y
8.'he *"re shown is a si*nal s!ace dia*ram for a. U"adrat"re USP %. :inary GSP c. :i-!hase SP d. SP
0.Le*atie feed%ac3 in am!liers a. Im!roes the si*nal to noise ratio at the in!"t %. im!roes the si*nal to noise ratio at the o"t!"t c. $oes not a
1.O"t!"t res!onse of a diode cli!!er circ"it shown in *"re will %e
2.Gor an L-channel OSGE' if cond"ction !arameter (3 n) is 0.28 m5,+ 2 *ate to so"rce olta*e + US is 2 + 'L where + 'L D 0.= olts. 'he c"rrent will %e a. 0.160 m5 %. 0.10 m5 c. 0.10 m5 d. 0.1=0 m5
.If D 0.8; I BO D 6 5 and I R D 100 5 for a transistor then the al"e of I B will %e a. 2. m5 %. .1 m5 c. .6 m5 d. .2 m5
.5 "nit ste! olta*e 2"(t- θ) is a!!lied in a series RB circ"it with R D 2N B D 1 G. ass"min* 7ero initial conditions nd i(t)
.'he a"to correlation of a wide sense stationary random !rocess is *ien %y e 2IWI . 'he !ea3 al"e of the s!ectral density is a. 2 %. 1 c. e-1,2 d. e
6.which of the followin* *ies !ie7o electric e
d. Gerrite
=.'he mean free !ath for electron drift increases with a. "rity %. Strain hardenin* c. Elastic mod"les d. Lone of the a%oe
;."re metals *enerally hae a. Hi*h cond"ctiity Q Xow tem!erat"re coeYcient %. Hi*h cond"ctiity Q Hi*h tem!erat"re coeYcient c. Xow cond"ctiity Q Zero tem!erat"re coeYcient d. Xow cond"ctiity Q Hi*h tem!erat"re coeYcient
8.5 ty!ical o!tical %er has a. Hi*h refractie inde? core Q low refractie inde? claddin* %. Xow refractie inde? core Q Hi*h refractie inde? claddin* c. Vniform refractie inde? core s"rro"nded %y aria%le refractie inde? claddin* d. Lone of the a%oe
0.'he ceramic materials are a. Inor*anic s"%stances %. :rittle c. >ood thermal ins"lators d. 5ll of the a%oe
1.'he %est denition of a s"!ercond"ctor is a. It is a material showin* !erfect cond"ctiity and eissner e
2.5 !eriodic f"nction of half wae symmetry is necessarily a. 5n een f"nction %. 5n odd f"nction c. Leither odd nor een
d. :oth odd and een
.'he Go"rier transform of a >a"ssian time !"lse is a. Vniform %. 5 !air of im!"lses c. >a"ssian d. Raylei*h
.'he coariance f"nction B ?(W) of a stationary stochastic !rocess ?(t) is said to %e !ositie denite. 'his means that
.If a ertical di!ole antenna is "sed in conM"nction with a loo! antenna for direction ndin* the eld !attern o%tained will %e
6.'he codin* system ty!ically "sed in di*ital telemetry is a. (!"lse !osition mod"lation) %. 5 (!"lse am!lit"de mod"lation) c. B ("lse code mod"lation) d. $ ("lse d"ration mod"lation)
=.'he tem!erat"re coeYcient of resistance for a thermistor is a. Xow and ne*atie %. Xow and !ositie c. Hi*h and ne*atie d. Hi*h and !ositie
;.Bom!ared to eld e
8.5 "niform !lane wae in air im!in*e at o an*le on a loss less dielectric material with dielectric constant [ r. 'he transmitted wae !ro!a*ates I a 0 o direction with res!ect to the normal. 'he al"e of [ r is
a. %. c. d.
1. \1. 2 \2
60.If a donor ty!e im!"rity is added to the semicond"ctor then at a *ien tem!erat"re the Germi leel a. oes towards the center of the ener*y *a! %. oes towards the alence %and c. oes towards the cond"ction %and d. $oesnTt chan*e
61. /hich of the followin* statement is correct# a. In semicond"ctors electron and holes moe in an electric eld and in the same direction %. Electric eld density is e?actly e&"al to the s"m of electric eld intensity and !olari7ation c. 5m!ereTs circ"ital law states that the line inte*ral of H a%o"t any closed !ath is e?actly e&"al to the direct c"rrent enclosed %y that !ath d. Lone of the a%oe 62.a*netic eld intensity (H) in 5,m with in a ma*netic material where D 10 5,m D 1. ? 10 - H,m r D 0] a. 1.821 %. 1.1; c. 1.;2 d. 1.=1
6.5 steel !i!e is constr"cted of a material for which r D 200 and ^ D ?10 6 mho,m. the o"ter and inner radii are ; and 6 mm res!ectiely and the len*th is ;0m. if the total c"rrent carried %y the !i!e is 2 cos10 πt 5m!. 'hen the s3in de!th will %e a. 0.22 ? 10- m %. 0.00 ? 10- m c. 0.2 ? 10- m d. 0.12 ? 10- m
6.5 small amo"nt of !hos!horo"s is added to silicon so that here are 2.?10 1= cond"ction electrons !er c"%ic meter and 8.0?10 1 holes !er c"%ic meter. Xet e D 0.1 m 2,+-sec and h D 0.0 m2,+-sec. 'he resistiity in N-m will %e a. .20=2 %. 182.02
c. 128.02 d. 0
6.Silicon dio?ide is "sed in IBs a. :eca"se it facilitates the !enetration of di<"rants %. :eca"se of its hi*h heat cond"ction c. 'o control the location of di<"sion and to !rotect and ins"late the Si s"rface d. 'o control the concentration of di<"rants
66.Eal"ate the *ien inte*ral.
6=.:oth transistor '1 and '2 in *"re hae a threshold olta*e of 1 olt. 'he deice !arameters P1 and P2 of '1 and '2 are 6 5,+ 2 and 8 5,+2 res!ectiely. 'he o"t!"t olta*e + o is a. 1 olt %. 2 olt c. olt d. olt
6;.5 ram! in!"t a!!lied to a "nity feed%ac3 system res"lts in steady state error. 'he ty!e n"m%er and 7ero fre&"ency *ain of the system are a. 1 and 20 %. 0 and 20 c. 0 and 1,20 d. 1 and 1,20
68.'he ma*nit"de of fre&"ency res!onse of an "nder sam!led second order system is at 0 rad,sec and !ea3s at 10,\ at \2 rad,sec. the transfer f"nction of the system is
=0.'he system with the o!en loo! transfer f"nction >(s)H(s) D 1,s(s 2 s 1) has a *ain mar*in of a. 9 6 d: %. Zero c. . d: d. 6 d:
=1.'he al"e of 3 for the *ien f"nction f(t) a. 1 %. 2 c. d.
=2.5 !erson on tri! has a choice %etween !riate car and !"%lic trans!ort. 'he !ro%a%ility of "sin* a !riate car is 0.. /hile "sin* !"%lic trans!ort f"rther choice aaila%le are %"s and metro. O"t of which the !ro%a%ility of comm"tin* %y a %"s is 0.. In s"ch a sit"ation the !ro%a%ility (ro"nded "! to two decimals) of "sin* car %"s and metro res!ectiely wo"ld %e a. 0. 0.0 and 0.2 %. 0. 0.2 and 0.0 c. 0. 0. and 0 d. 0. 0. and 0.20
=.5 real root of e&"ation ? 9 ? 9 = D 0 %y the method of false !osition correct to three decimal !laces is a. 2.==2 %. 2.0; c. 2.0== d. Lone of the a%oe
=.Gind the 7-transform of cosh(n θ)
=.Lewton 9 Ra!hson iteration form"la for ndin* =6.'he al"e of ==.Gind the al"es of P $ P and P I for I$ controller res!ectiely whose characteristics e&"ation has real roots at 10 ζ = 0.8 and ω= 2 rad/sec a. 1.; ; 10 %. 1.; c. .6 ; 20 d. 1.; ; 20
=;.'he transfer f"nction (1 0.s) , (1 s) re!resents a a. Xa* networ3
%. Xead networ3 c. Xa*-lead networ3 d. ro!ortional controller
=8.'he waelen*th of emitted radiation %y electron while transmittin* from one ener*y state of -1 e+ to other ener*y state of 9 e+ is a. 1000 5o %. 120 5o c. 12;0 5o d. 100 5o
;0.5ccordin* to ma?im"m !ower transfer theorem ma?im"m !ower transfer occ"rs when a. Xoad R is e&"al to the half the R of the networ3 %. Xoad R is e&"al to twice the R of networ3 c. Xoad R is e&"al to the R of networ3 loo3in* %ac3 at it from olta*e terminal d. Xoad R is e&"al to the R of networ3 loo3in* %ac3 at it from load terminals with all so"rces %ein* re!laced %y their res!ectie internal resistance.
